The present invention generally relates to the field of tissue sampling and harvesting. The invention more specifically relates to biopsy guns and needles.
Examples of typical double action biopsy guns are described in U.S. Pat. Nos. 4,699,154; 4,944,308; 5,284,156 and 6,221,030. Prior art biopsy guns are well known and widely used, but they suffer from certain significant drawbacks. For example, know prior art double action biopsy guns require the use of two hands. This is unfortunate because the tissue sampling is typically performed under visualization, such as ultra sound. It would be convenient to have a free hand to operate the visualization equipment. Many devices also make a compromise between sample quality and cocking force. To achieve significant needle velocity, prior art devices have required significant cocking force. To reduce cocking force has meant poorer sample quality.
Therefore, a need remains for double action biopsy guns that can be cocked and fired using a single hand yet which reliably provide high quality tissue samples.